Depending on how big you want it to be, you could also do a chocolate transfer which is almost identical to FBCT except you're using chocolate. It's easiest with candy melts - you could buy white and add candy color to them. Then you pipe the outline of your design as well as the fine details, let that set, and then fill in. There are a bunch of tutorials on chocolate transfers in the forums. You could do it as big as you want but chocolate tends to be fragile / brittle so you'd need to make it nice and thick so it doesn't break when you're putting it on the cake. Chocolate transfers, too, need to be piped "in reverse" meaning that if you didn't reverse your image, when you flipped over your transfer it would be the opposite of what you piped.